1. Technical Field
The disclosure relates to a lens unit and a light source module with the lens unit.
2. Discussion of Related Art
Light emitting diodes (LEDs) with many advantages, such as high luminosity, low operational voltage, low power consumption, compatibility with integrated circuits, faster switching, long term reliability, and environmental friendliness have promoted their wide use as a lighting source.
However, the conventional LED cannot have a wide illumination area even use with a diverging lens. The light having a large incidence angle on the light emerging face of the diverging lens, may be totally reflected backwardly into the diverging lens. Thus, the radiation angle of the light emitted out of the diverging lens is limited, generally less than 120 degrees. In other words, the light intensity dramatically decreases when the radiation angle exceeds 120 degrees.
Therefore, what is needed is a lens unit and a light source module with the lens which can overcome the described limitations.